The dynamics of rooting in Triplochiton scleroxylon cuttings: their relation to leaf area, node position, dry weight accumulation, leaf water potential and carbohydrate composition

Partitioning of water resources amongst plant species within a single climate envelope is possible if the species differ in key hydraulic traits. We examined 11 bivariate trait relationships across nine woody species found in the Ti-Tree basin of central Australia. We found that species with limited access to soil moisture, evidenced by low pre-dawn leaf water potential, displayed anisohydric behaviour (e.g. large seasonal fluctuations in minimum leaf water potential), had greater sapwood density and lower osmotic potential at full turgor. Osmotic potential at full turgor was positively correlated with the leaf water potential at turgor loss, which was, in turn, positively correlated with the water potential at incipient stomatal closure. We also observed divergent behaviour in two species of Mulga, a complex of closely related Acacia species which range from tall shrubs to low trees and dominate large areas of arid and semiarid Australia. These Mulga species had much lower minimum leaf water potentials and lower specific leaf area compared with the other seven species. Finally, one species, Hakea macrocarpa A.Cunn ex.R.Br., had traits that may allow it to tolerate seasonal dryness (through possession of small specific leaf area and cavitation resistant xylem) despite exhibiting cellular water relations that were similar to groundwater-dependent species. We conclude that traits related to water transport and leaf water status differ across species that experience differences in soil water availability and that this enables a diversity of species to exist in this low rainfall environment.

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Vertical Wilting and Photosynthesis, Transpiration, and Water Use Efficiency of Sunflower Leaves

Functional Plant Biology ◽

10.1071/pp9790109 ◽

1979 ◽

Vol 6 (1) ◽

pp. 109 ◽

Cited By ~ 18

Author(s):

HM Rawson

Keyword(s):

Water Use Efficiency ◽

Water Potential ◽

Water Use ◽

Leaf Water Potential ◽

Stomatal Closure ◽

Net Photosynthesis ◽

Leaf Water ◽

Vertical Orientation ◽

Use Efficiency ◽

Node Position

Plants of two sunflower cultivars were exposed to a number of soil drying cycles and the gas exchange of young, fully expanded leaves at different nodes was measured continuously from when the leaves were turgid until when they were severely and vertically wilted. Peak rates of net photosynthesis increased with the height of leaf insertion but, regardless of node position, leaves at vertical wilting always had rates of net photosynthesis which were close to 50% of peak rates. Although the leaf water potential at which vertical wilting occurred ranged between - 1.3 and -2.2 MPa and varied even for a particular leaf position, there was a similar relationship between the rate of reduction in photosynthesis and the reduction in leaf water potential. No evidence was found for a threshold leaf water potential at which stomatal closure occurs. Water use efficiency improved when leaves changed from a horizontal to a vertical orientation, apparently through changes in leaf temperature but. by the stage of wilting, water use efficiency had already markedly improved over efficiencies of turgid leaves. Much of this improvement stemmed from changes in leaf conductances. No clear differences between cultivars were evident in any parameter measured. The likely effects that wilting will have on water use efficiency in the field and strategies for optimising water use on a diurnal basis are discussed.

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Rootstock Genotypes Shape the Response of cv. Pinot gris to Water Deficit

Agronomy ◽

10.3390/agronomy11010075 ◽

2020 ◽

Vol 11 (1) ◽

pp. 75

Author(s):

Michele Faralli ◽

Pier Lugi Bianchedi ◽

Massimo Bertamini ◽

Claudio Varotto

Keyword(s):

Water Stress ◽

Water Potential ◽

Leaf Area ◽

Water Use ◽

Leaf Water Potential ◽

Water Availability ◽

Leaf Water ◽

Daily Water ◽

Shallow Soils ◽

Reduced Water

Understanding the physiological basis underlying the water stress responses in grapevine is becoming increasingly topical owing to the challenges that climate change will impose to grapevine agriculture. Here we used cv. Pinot gris (clone H1), grafted on a series of tolerant (1103Paulsen; P), sensitive (SO4) and recently selected (Georgikon28; G28, Georgikon121; G121, Zamor17; Z17) rootstocks. Plants were either subjected to reduced water availability (WS) or maintained at pot capacity (WW). Photosynthetic (light response curves), stomatal and in vivo gas exchange analysis were carried out as well as dynamics of daily water use (WU), leaf area accumulation with affordable RGB imaging pipelines and leaf water potential. Significant genotypic variation was recorded between rootstocks for most of the traits analyzed under optimal conditions with P and SO4 showing a more vigorous growth, higher CO2 assimilation rate, stomatal conductance and stomatal density per unit of leaf area than G28, G121, Z17 (p < 0.001). Under WS, rootstocks induced different water stress response in Pinot gris, with G28 and G121 showing a higher sensitivity of water use to reduced water availability (WS) (p = 0.021) and no variation for midday leaf water potential until severe WS. P, Z17 and to some extent SO4 induced a pronounced near-anisohydric response with a general WU maintenance followed by reduction in leaf water potential even at high levels of soil water content. In addition, G28 and G121 showed a less marked slope in the linear relationship between daily water use and VPD (p = 0.008) suggesting elevated sensitivity of transpiration to evaporative demand. This led to an insensitivity for total dry weight biomass of G28 and G121 under WS conditions (p < 0.001). This work provides: (i) an in-depth analysis for a series of preferable traits under WS in Pinot gris; (ii) a characterization of Pinot gris × rootstock interaction and a series of desirable traits under WS induced by several rootstocks; (iii) the potential benefit for the use a series of affordable methods (e.g., RGB imaging) to easily detect dynamic changes in biomass in grapevine and quickly phenotype genotypes with superior responses under WS. In conclusion, the near-isohydric and conservative behavior observed for G28 and G121 coupled with their low vigor suggest them as potential Pinot gris rootstock candidates for sustaining grapevine productivity in shallow soils likely to develop terminal stress conditions.

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TRANSPLANTING AND ORGANIC MULCH AFFECT GAS EXCHANGE AND GROWTH OF FIELD GROWN RED OAK (QUERCUS SHUMARDII BUCKLI.)

HortScience ◽

10.21273/hortsci.41.3.497c ◽

2006 ◽

Vol 41 (3) ◽

pp. 497C-497 ◽

Cited By ~ 1

Author(s):

Amber Bonds ◽

Thayne Montague

Keyword(s):

Gas Exchange ◽

Water Potential ◽

Leaf Area ◽

Leaf Water Potential ◽

Growing Season ◽

Leaf Water ◽

Red Oak ◽

Predawn Leaf Water Potential ◽

Organic Mulch ◽

Quercus Shumardii

Balled in burlaped is a common method for moving large trees into landscapes and affects of transplanting on tree gas exchange and growth has been documented. Organic mulch provides many benefits and is often recommended for landscapes. Because little research has been conducted on affects organic mulch has on gas exchange and growth of transplanted and non-transplanted trees, this research investigated the effects transplanting and organic mulch have on gas exchange and growth of field grown red oak (Quercus shumardii) trees. In March 2003, 12 multi-trunked trees were selected from a tree farm near Lubbock, Texas, and six trees were dug using a tree spade and placed in their original location. Mulch at a depth of 10 cm was placed around the rootball of 3 transplanted and 3 nontransplanted trees and maintained at this depth the remainder of the experiment. Over the next three growing seasons predawn leaf water potential and midday stomatal conductance were measured on each tree every 1 to 3 weeks. At the end of every growing season shoot elongation, stem caliper and subsample leaf area were recorded. Our data indicates transplanting has a negative affect on gas exchange and growth of red oak. Each growing season gas exchange, shoot growth, and subsample leaf area were less for transplanted trees when compared to nontransplanted trees. Mulch also influenced gas exchange and growth of these trees. For nontransplanted trees with mulch, gas exchange and growth were reduced when compared to nonmulched, nontransplanted trees. For transplanted trees with mulch, predawn leaf water potential was less negative and subsample leaf area was greater when compared to transplanted trees with out mulch.

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Yield and components of seed yield of indeterminate narrow-leafed lupin (Lupinus angustifolius L.) subjected to transient water deficit

Australian Journal of Agricultural Research ◽

10.1071/ar97162 ◽

1999 ◽

Vol 50 (7) ◽

pp. 1225 ◽

Cited By ~ 7

Author(s):

J. A. Palta ◽

Z. Plaut

Keyword(s):

Water Potential ◽

Leaf Area ◽

Water Deficit ◽

Leaf Water Potential ◽

Seed Yield ◽

Dry Matter ◽

Leaf Conductance ◽

Leaf Water ◽

Water Deficits ◽

Pod Number

The effect of transient water deficits on seed yield and components of seed yield of narrow-leafed lupin was measured in plants grown in a controlled environment under simulated field conditions. Lupins were grown in large columns of soil and transient water deficits were induced at pod set on the mainstem and first-order apical branches by withholding water for a 5-day period. Soil water content, leaf water potential, turgor pressure, and leaf conductance declined similarly during each period of transient water deficit. Differences in these parameters were apparent 2 days after water was withheld, and over the 5-day period, leaf water potential declined to −1.3 MPa and leaf conductance fell to 44% of the well-watered controls. Total dry matter per plant was reduced by the transient water deficit treatments. The reduction resulted from less accumulation of dry matter on the first, second, and third order apical branches. Leaf area on these branches was also reduced by abscission of the leaves after the water deficit was released. Seed yield per plant after each period of transient water deficit was reduced by 30–33%, relative to the well-watered controls. The reduction was largely due to a reduction in seed yield on the branches, mainly because they had fewer pods and seeds per pod. Seed dry weight and harvest index were not significantly affected by each period of transient water deficit. We conclude that differences in final seed yield between the well- watered controls and the transient water deficit treatments resulted from differences in pod number and seeds per pod. Low dry matter accumulation and reduction in leaf area on the first- and second-order apical branches under the transient water deficit were associated with the differences. Whereas the differences in pod number generated differences in the size of the reproductive sink, the differences in leaf area generated differences in the source capacity for assimilates for pod set and pod-filling.

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Differences between tree species in hydraulic press calibration of leaf water potential are correlated with specific leaf area.

Plant Cell & Environment ◽

10.1111/1365-3040.ep11591871 ◽

1984 ◽

Vol 7 (8) ◽

pp. 597-600 ◽

Cited By ~ 1

Author(s):

E. Raymond Hunt, Jr. ◽

James A. Weber ◽

David M. Gates

Keyword(s):

Water Potential ◽

Leaf Area ◽

Leaf Water Potential ◽

Specific Leaf Area ◽

Tree Species ◽

Hydraulic Press ◽

Leaf Water ◽

Press Calibration

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INFLUENCE OF SOIL DENSITY ON LEAF WATER POTENTIAL OF CORN

Canadian Journal of Soil Science ◽

10.4141/cjss78-032 ◽

1978 ◽

Vol 58 (2) ◽

pp. 275-278

Author(s):

D. T. MORRIS ◽

T. B. DAYNARD

Keyword(s):

Root Growth ◽

Water Potential ◽

Bulk Density ◽

Leaf Area ◽

Leaf Water Potential ◽

Soil Bulk Density ◽

Leaf Water ◽

Soil Density ◽

Water Potentials ◽

Corn Plants

Corn plants were grown in growth rooms at 1.2 and 1.4 g cm−3 soil bulk density. Leaf water potentials (LWP) of paired plants of similar leaf area were monitored during 3-day drying cycles. With denser soil, LWP declined more rapidly during light, and increased more slowly during dark intervals because of restricted root growth.

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Effects of Water Deficits on Prosopis tamarugo Growth, Water Status and Stomata Functioning

Plants ◽

10.3390/plants10010053 ◽

2020 ◽

Vol 10 (1) ◽

pp. 53

Author(s):

Alson Time ◽

Edmundo Acevedo

Keyword(s):

Stomatal Conductance ◽

Water Potential ◽

Leaf Area ◽

Water Deficit ◽

Leaf Water Potential ◽

Growth Parameters ◽

Water Status ◽

Co2 Assimilation ◽

Leaf Water ◽

Ww Ii

The effect of water deficit on growth, water status and stomatal functioning of Prosopis tamarugo was investigated under controlled water conditions. The study was done at the Antumapu Experiment Station of the University of Chile. Three levels of water stress were tested: (i) well-watered (WW), (ii) medium stress intensity (low-watered (LW)) and (iii) intense stress (non-watered (NW)), with 10 replicates each level. All growth parameters evaluated, such as twig growth, specific leaf area and apical dominance index, were significantly decreased under water deficit. Tamarugo twig growth decreased along with twig water potential. The stomatal conductance and CO2 assimilation decreased significantly under the water deficit condition. Tamarugo maintained a high stomatal conductance at low leaf water potential. In addition, tamarugo reduced its leaf area as a strategy to diminish the water demand. These results suggest that, despite a significant decrease in water status, tamarugo can maintain its growth at low leaf water potential and can tolerate intense water deficit due to a partial stomatal closing strategy that allows the sustaining of CO2 assimilation in the condition of reduced water availability.

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Flooding, Leaf Gas Exchange, and Growth of Mango in Containers

Journal of the American Society for Horticultural Science ◽

10.21273/jashs.116.1.156 ◽

1991 ◽

Vol 116 (1) ◽

pp. 156-160 ◽

Cited By ~ 23

Author(s):

Kirk D. Larson ◽

Bruce Schaffer ◽

Frederick S. Davies

Keyword(s):

Gas Exchange ◽

Water Potential ◽

Leaf Water Potential ◽

Vegetative Growth ◽

Tree Mortality ◽

Leaf Gas Exchange ◽

Mangifera Indica ◽

Dry Weight ◽

Leaf Water ◽

Soil Conditions

The effect of flooding on container-grown `Tommy Atkins' mango (Mangifera indica L.) trees on two rootstock, and on container-grown seedling `Peach' mango trees, was investigated by evaluating vegetative growth, net gas exchange, and leaf water potential. In general, flooding simultaneously reduced net CO2 assimilation (A) and stomatal conductance (gs) after 2 to 3 days. However, flooding did not affect leaf water potential, shoot extension growth, or shoot dry weight, but stem radial growth and root dry weight were reduced, resulting in larger shoot: root ratios for flooded trees. Mortality of flooded trees ranged from 0% to 45% and was not related to-rootstock scion combination. Hypertrophied lenticels were observed on trees that survived flooding but not on trees that died. The reductions in gas exchange, vegetative growth, and the variable tree mortality indicate that mango is not highly flood-tolerant but appears to possess certain adaptations to flooded soil conditions.

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Response of Potted Peach Trees to Pruning and Grass Competition

HortScience ◽

10.21273/hortsci.35.7.1209 ◽

2000 ◽

Vol 35 (7) ◽

pp. 1209-1212 ◽

Cited By ~ 3

Author(s):

Thomas Tworkoski

Keyword(s):

Water Potential ◽

Leaf Area ◽

Leaf Water Potential ◽

Festuca Arundinacea ◽

Fine Roots ◽

Growth Response ◽

Shoot Growth ◽

Prunus Persica ◽

Leaf Water ◽

Peach Trees

Peach [(Prunus persica (L.) Batsch., `Rutgers Redleaf'] trees were grown for two seasons in a greenhouse with three pruning treatments (none, shoot tips removed, and half the shoots removed) and three grass treatments (no grass competition; perennial ryegrass, Lolium perenne L., `Linn'; and tall fescue, Festuca arundinacea Schreb, `Kentucky 31'). Competing grass reduced shoot growth, leaf area, and weight of fine roots in shallow soil, but did not affect the growth response to pruning. Regrowth from pruned trees was such that the shoot: root ratio was restored to that of unpruned trees. Leaf water potential, stomatal conductance, and photosynthesis had decreased markedly by 48 hours after irrigation ceased in trees without competition (larger trees) and to a similar level by 96 hours in trees with competition (smaller trees). Apparently, the reduced leaf area of peach trees grown with grass competition delayed water stress. Leaf abscisic acid levels were not directly affected by grass competition but increased as leaf water potential decreased. Grass competition modified morphology and reduced tree size, but did not affect shoot growth following pruning.

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